Aetna CEO: Obamacare In A 'Death Spiral' Heading Into 2018. Aetna and Humana have called off their deal amid government concerns over competition. Here's a look back at six pivotal moments that led to this. Aetna and Humana have called off their deal amid government concerns over competition.
For the plant genus, see Synapsis (plant). Synapsis (also called syndesis) is the pairing of two homologous chromosomes that occurs during meiosis. It allows matching-up of homologous pairs prior to their segregation, and possible chromosomal crossover between them. Synapsis takes place during prophase I of meiosis.
To deal with this, synaptic pruning occurs as a result of the use or disuse of neurons during a babyâs experiences. (ones that arent used are eliminated) -the pruning allows for established neurons to build more elaborate communication networks with other neurons. -myelination mostly occurs within the first two years of life.